Flexible seal

ABSTRACT

A flexible seal for sealing between two members including a hollow body of resilient material which has a mounting wall portion formed therein which portion is securable to one of the members. A sealing wall portion is formed in the body which is disposed oppositely to the mounting wall portion and sealably engageable with the other member. A pair of spaced sidewalls are formed in the body which are readily deformable to permit installation of the seal with the sidewalls in a predetermined, deformed position so as to maintain biased sealing engagement during relative movement between the members.

United States Patent 1 Fidler et al.

[ Nov. 20, 1973 FLEXIBLE SEAL [7 5] Inventors: Carl E. Fidler,Chillicothe; John W.

Yancey, Aurora, both of Ill.

52 us. c1 ..277/9s,277/34.3,49/490 51 int. c: Fl6j 15/34 [58] Field ofSearch 49/490, 491,498;

[56] References Cited UNITED STATES PATENTS Breyfogle et a] 277/95Panhard 277/226 X Primary Examiner-Herbert F. Ross AssistantExaminer-Robert 1. Smith Attorney-Warren J. Krauss et al.

[ ABSTRACT A flexible seal for sealing between two members including ahollow body of resilient material which has a mounting wall portionformed therein which portion is securable to one of the members. Asealing wall portion is formed in the body which is disposed oppositelyto the mounting wall portion and sealably engageable with the othermember. A pair of spaced sidewalls are formed in the body which arereadily deformable to permit installation of the seal with the sidewallsin a predetermined, deformed position so as to maintain biased sealingengagement during relative movement between the members.

10 s. 2 aw F res FLEXIBLE SEAL BACKGROUND OF THE INVENTION Many largemechanisms, such as hydraulic excavators and cranes, employ a largebearing system to permit relative rotation between upper and lower framemembers. Such mechanisms generally have a formed sheet metal enclosuremeans which houses a rotating drive mechanism wherein one element of theenclosure means is attached to the upper frame member while anotherelement is attached to the lower frame member. Seals are disposedbetween the rotatable elements to preclude ingress of grit or otherforeign particles to the enclosure means and to retain lubricating fluidtherein.

A major problem encountered with such systems is that of leakage due toa tendency for such sheet metal components to have warped or wavysurfaces introduced during manufacturing thereof which surfaces resultin variations in spacing between the assembled components. These warpedor wavy surfaces and the required manufacturing tolerances for suchrotating mechanisms permit the spacing between the elements to fluctuateconsiderably during rotation. In some cases, such fluctuations betweenthe elements are of such magnitude that sealing contact is broken or thesealing member is compressed sufficiently to produce overstress withconsequent permanent deformation or premature failure.

OBJECTS OF THE INVENTION One of the objects of this invention is toprovide an improved flexible seal for sealing between a pair ofrelatively movable members.

Another object of this invention is to provide an improved flexible sealwhich can be installed in a partially-deformed condition between themembers to maintain a biased sealing contact with the members duringvariations in the spacing therebetween.

Yet another object of this invention is to provide an improved flexibleseal having a hollow, substantially rectangularly-shaped body ofresilient material which permits the seal to be deformed over a greaterrange than conventional seals while maintaining its sealingeffectiveness.

Other objects and advantages of the present invention will becomereadily apparent upon reference to the accompanying drawings andfollowing description.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of aflexible seal embodying the principles of the present invention showndisposed sealingly between two relatively rotatable members.

FIG. 2 is a cross-sectional view of the flexible seal in its free,undeformed state.

DETAILED DESCRIPTION Referring more particularly to the drawings, aflexible seal embodying the principles of the present invention isindicated generally by the reference numeral 10. The seal is disposedsealingly between a pair of members 11 and 12 which are only partiallyshown. The

1 members are elements of a circular sheet metal enclosure; member 11being rotatable relative to member 12. Due to inherent manufacturingtolerances and wavy surfaces introduced during manufacturing of suchsheet metal elements, the members exhibit a predetermined range offluctuation in radial and axial spacing therebetween during relativerotation.

The flexible seal comprises a hollow annular body having an annularpassage 14 formed therein. The annular body is made from a resilientmaterial such as rubber or other suitable flexible plastic material. Inits free form, as shown in FIG. 2, it has a substantially rectangularcross-sectional configuration. Part of the body forms a mounting wallportion 16 which includes a projection 17 centrally formed thereon whichprotrudes inwardly. An annular groove or recessl8 is formed within themounting wall portionand projection 17. This groove is formed wideracross at its inwardlyprojecting end than at its external end when theseal is in its free state, as shown in FIG. 2. This provides abias forfirm retention of the seal when installed.

A sealing wall portion 21 is formed on the body opposite to the mountingwall portion 16. As clearly shown in FIG. 2, the sealing wall portionhas an external concave surface 22 formed between a pair ofsymmetrically-disposed, generally-flat sealing surfaces 23.

The body further includes a pair of oppositelydisposed, spaced-apartsidewalls 26 and 27 which individually extend between and interconnectthe mounting wall portion 16 and sealing wall portion 21. The sidewallsare symmetrical and each has an undulatory shape defined by a concaveportion 28 proximal to the sealing wall portion and a convex portion 29proximal to the mounting wall portion.

It will be noted that the sidewalls 26 and 27 have a substantiallythinner cross-sectional configuration and consequently less flexurestrength than the closelyadjacent areas between the sidewalls at theupper and lower parts of the body. As further explained, hereinafter,this configuration provides for a high resistance to deformation and forshape retention in the strenghtened areas and for resilient biasingdeformation in the sidewalls.

Sealing surfaces 30 are formed on the upper extremity of each of thesidewalls. These surfaces together with respective sealing surfaces 23cooperate normally to form a pair of substantially rectangular edges 31and 32. The convex portions 29 form substantially curved comers betweenthe mounting wall portion and the sidewalls.

As best shown in FIG. 1, with the flexible seal 10 installed in asealing position between the members 11 and 12, the annular groove 18 ofthe mounting wall .portion 16 registers with member 12 in secure sealingrelation thereto. The aforementioned width differential between theinner and outer ends of the groove 18 assures a tight biased fit. Asshown, the edges 31 and 32 are in contact with member 11 and arecompressed so that both pairs of sealing surfaces 23 and 30 are inintimate sealing contact with the member. Such edge compression wouldoccur subsequent to deformation of the sidewalls 26 and 27 due to theaforementioned flexure strength and thickness configurations of thevarious parts of the body.

In an alternate installation, sealing contact could be made to occuronly between the sealing surfaces 23 and a member 11 arrangedsubstantially parallel to the seal-' ing wall portion 21. Anotherinstallation arrangement for the seal could have the sealing wallportion arranged in a grooved member wherein sealing contact would occurbetween both pairs of sealing surfaces and the member withoutdeformation of the edges 31 and 32.

The seal is installed preferably in a predetermined deformed conditionwherein the sealing wall portion is forced toward the mounting wallportion by the member 11. In this condition, the seal accommodates apredetermined range of multi-directional fluctuations in spacing betweenthe members while maintaining sealing contact with the member 1 1. Forexample, if one of the members moves away from the other member, thebiased resiliency of the seal sidewalls causes the sealing wall portionto move in a direction away from the mounting wall portion so that thesealing wall portion remains in contact with the member 11. The instantflexible seal is deformable beyond the predetermined deformedinstallation condition so as to accommodate movement of the members in adirection toward each other without overstressing the seal.

As noted previously, the major portion of the deformation in theflexible seal occurs in the sidewalls 26 and 27, and the undulatoryshape of the sidewalls provides a preshape to provide a predetermineddirection of the deformation. The symmetrical shape of the sidewallsinsures substantially equal resistance to such deformation and constantsealing pressure between the sealing surfaces and the member 11 over apredetermined range. of seal deformations.

In view of the foregoing, it is readily apparent that the I structure ofthe present invention provides an improved flexible seal for sealingbetween a pair of relatively movable members which are subjected tovariations in the spacing therebetween. The flexible seal utiizes aresilient hollow body which has readily deformable sidewalls to permitinstallation thereof in a predetermined deformed condition such thatbiased sealing contact with. the members is maintained during suchvariations in spacing between the members.

While the invention has been described and shown with particularreference to the preferred embodiment, it will be apparent thatvariations are possible within the spirit of the inventive concepts andthat no limitation is intended, except by the scope of the appendedclaims.

What is claimed is:

l. A flexible seal, for sealing between relatively disposed movablemembers, comprising; a hollow body means of resilient material, saidbody means having a mounting wall portion formed thereon for secureenwall portion including groove means formed therein for registry withone of said members, a sealing wall portion formed on said body meanssubstantially oppositely disposed with respect to said mounting wallportionand sealably engageable with another of said members, and saidbody means including a pair of spaced sidewall means formed between saidmounting wall portion and said sealing wall portion, said sidewall meansbeing readily deformable for permitting the installation of saidflexible seal between said members with said sidewall means in apredetermined deformed condition to maintain biased sealing contactduring predetermined relative movement between said members in multipledirections, each of said sidewall means gagement with one of saidmembers, said mounting having a concave portion adjacent to said sealingwall portion and a convex portion adjacent to said mounting wall portionforming an undulatoryshape for'preshaping the sidewall means to controlthe direction of deformation thereof. j l

2. The flexible seal of claim 1. wherein saidsealing wall portionincludes a first pair of -spaced flat sealing contact surfacesindividually operatively associated with said sidewall means.

3. The flexible seal of claim 2 wherein said body means has a thickercross-sectional,configuration at said areas adjacent to said sealingcontact surfaces than in said sidewall means. I 1 v.

4. The flexible seal of claim 2 wherein said sidewall means include asecond pair of spaced sealing contact surfaces juxtaposed to said firstpair of flat sealing contact surfaces.

5. The flexible seal of claim 1 wherein said mounting wall portionincludes an annular projection which protrudes inwardly within saidhollow body means.

6. The flexible seal of claim 1-wherein said groove means are wider atone end thereof than at the other.

7. A flexible seal, for sealing between relatively disposed movablemembers, comprising; a hollow body means of resilient meaterial having asubstantially rectangular cross section, mounting wall means formed onsaid body means and having mounting means therein for engagement withone of said members, said mounting means including groove means, sealingwall means formed on said body means substantially oppositely disposedto said mounting wall means and sealably engageable with another of saidmembers, and a pair of sidewall means formed on said body means, saidsidewall means being disposed between and interconnecting said mountingwall means and said sealing wall means, said sidewall means beingreadily deformable and having an undulatory shape which causes inwarddeformation adjacent to said sealing wall means and outward deformationof said sidewall means adjacent said mounting wall means for readilydeforming to permit installation of said seal between said members withsaid sidewall means in a predetermined deformed condition to maintainbiased sealing contact with said members during multi-directionalrelative movement therebetween.

8. The flexible seal of claim 7 wherein said sealing wall means includein undeformed condition a centrally-disposed concave portion and a pairof flat sealing contact surfaces individually disposed on opposite sidesof said concave portion.

9. The flexible seal of claim 8 wherein said mounting means include anannular groove formed in said mounting wall means for registry with oneof said members.

10 The flexible seal of claim 9 wherein said undulatory shape of each ofsaid sidewall means is formed by a concave portion adjacent to saidsealing wall means and a convex portion adjacent to the mounting wallmeans to provide a'predetermined direction of deformation of saidsidewall means, and wherein said sidewall means are symmetrical toprovide substantially equal resistance to deformation.

1. A flexible seal, for sealing between relatively disposed movable members, comprising; a hollow body means of resilient material, said body means having a mounting wall portion formed thereon for secure engagement with one of said members, said mounting wall portion including groove means formed therein for registry with one of said members, a sealing wall portion formed on said body means substantially oppositely disposed with respect to said mounting wall portion and sealably engageable with another of said members, and said body means including a pair of spaced sidewall means formed between said mounting wall portion and said sealing wall portion, said sidewall means being readily deformable for permitting the installation of said flexible seal between said members with said sidewall means in a predetermined deformed condition to maintain biased sealing contact during predetermined relative movement between said members in multiple directions, each of said sidewall means having a concave portion adjacent to said sealing wall portion and a convex portion adjacent to said mounting wall portion forming an undulatory shape for preshaping the sidewall means to control the direction of deformation thereof.
 2. The flexible seal of claim 1 wherein said sealing wall portion includes a first pair of spaced flat sealing contact surfaces individually operatively associated with said sidewall means.
 3. The flexible seal of claim 2 wherein said body means has a thicker cross-sectional configuration at said areas adjacent to said sealing contact surfaces than in said sidewall means.
 4. The flexible seal of claim 2 wherein said sidewall means include a second pair of spaced sealing contact surfaces juxtaposed to said first pair of flat sealing contact surfaces.
 5. The flexible seal of claim 1 wherein said mounting wall portion includes an annular projection which protrudes inwardly within said hollow body means.
 6. The flexible seal of claim 1 wherein said groove means are wider at one end thereof than at the other.
 7. A flexible seal, for sealing between relatively disposed movable members, comprising; a hollow body means of resilient meaterial having a substantially rectangular cross section, mounting wall means formed on said body means and having mounting means thErein for engagement with one of said members, said mounting means including groove means, sealing wall means formed on said body means substantially oppositely disposed to said mounting wall means and sealably engageable with another of said members, and a pair of sidewall means formed on said body means, said sidewall means being disposed between and interconnecting said mounting wall means and said sealing wall means, said sidewall means being readily deformable and having an undulatory shape which causes inward deformation adjacent to said sealing wall means and outward deformation of said sidewall means adjacent said mounting wall means for readily deforming to permit installation of said seal between said members with said sidewall means in a predetermined deformed condition to maintain biased sealing contact with said members during multi-directional relative movement therebetween.
 8. The flexible seal of claim 7 wherein said sealing wall means include in undeformed condition a centrally-disposed concave portion and a pair of flat sealing contact surfaces individually disposed on opposite sides of said concave portion.
 9. The flexible seal of claim 8 wherein said mounting means include an annular groove formed in said mounting wall means for registry with one of said members.
 10. The flexible seal of claim 9 wherein said undulatory shape of each of said sidewall means is formed by a concave portion adjacent to said sealing wall means and a convex portion adjacent to the mounting wall means to provide a predetermined direction of deformation of said sidewall means, and wherein said sidewall means are symmetrical to provide substantially equal resistance to deformation. 